INPUT DEVICES


Instructions to upload your contribution:
1. Click on EDIT (top right tab)
2. Write your name in brackets (for example [Maria Jose Mora])
3. Write a title with the name of your component
4. Copy the information you wrote in your word document
5. Upload no more than three pictures from the ones saved in the hub.
6. Write all the websites you used for your research.
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[ Shobana Gurusubramanian]

How do digital and video cameras work?

When a picture is taken using a digital camera, the camera must change light into electrons to capture the image in a digital format. The image first enters the camera through the lens. The light from the image is then focused onto a plane inside the camera where a silicon chip, known as a sensor, absorbs it. The sensor is covered by photo sites, which are light-sensitive areas that are usually shaped like squares. These photo sites will convert the light into electrons. Photo sites are sometimes called pixels. They are arranged in rows and columns, and the number of pixels determines the resolution of the camera. If you have a camera that has a sensor with 3,008 horizontal pixels and 2,000 vertical pixels in its grid, you will have 6,016,000 total pixels in the camera. This would be a six mega pixel camera. Storing the Image

The filters adjust the white and color balances. Then, the image is packed in by removing unnecessary pixels. It is then stored in this packed together and filtered form. The first storage place is a cushion inside the camera. This cushion holds images for the time being and when it fills up, the images are then transferred to the digital storage media, which is usually a memory card. The cushion allows the user to take multiple images quickly. A camera with a small cushion will have a long wait time between straight pictures. After the image is on the digital memory card, it is ready to be printed, sent passing through email, or uploaded to the Internet. Digital and video cameras are inputs. By: Shobana [[http://www.ehow.com |www.ehow.com ]]
images....jpg

(Daan Weijs)


microphones


Microphones

Basics
There are many different types of computer microphones, but all of them work in the same basic way. Inside the microphone is a diaphragm, a screen which is sensitive to pressure waves. When you make a sound, it creates waves of pressure in the air, which push on the diaphragm. When the diaphragm moves, it produces an electric signal, which is sent to the computer sound card.



Audio-to-Digital Converter

The sound card takes the audio signal and turns it into a digital signal. It does this by taking many digital "snapshots" of the signal. The signal comes in as a wave. Thousands of times a second, the computer records the value of the sound wave as a number. Between all of the readings, it can make an extremely detailed picture of the sound wave.



Digital-to-Analog Converter

When you are ready to listen to the recording, the computer converts the digital signal back into a sound wave. The computer takes all of those individual signals and creates an almost exact copy of the original sound wave. That copy is made into an electronic signal, which is sent to the computer speakers, which play the computer microphones
computer-microphone[1].jpg

http://www.ehow.com/how-does_4691185_computer-microphone-work.html
http://www.google.co.ug/imgres?imgurl=http://www.the-microphone-guide.com/images/computer-microphone.jpg&imgrefurl=http://www.the-microphone-guide.com/computer-microphone.html&usg=__SJ2kTNRG2lq4u5NDZ1_T5MxXE_A=&h=200&w=200&sz=17&hl=en&start=0&zoom=1&tbnid=7K5fkwPnqU8YlM:&tbnh=123&tbnw=123&prev=/images%3Fq%3Dcomputer%2Bmicrophones%26hl%3Den%26sa%3DX%26gbv%3D2%26biw%3D871%26bih%3D416%26tbs%3Disch:1&itbs=1&iact=hc&vpx=148&vpy=123&dur=16&hovh=160&hovw=160&tx=72&ty=90&ei=vzaHTM-sHY2eOLnHoJIO&oei=vzaHTM-sHY2eOLnHoJIO&esq=1&page=1&ndsp=10&ved=1t:429,r:0,s:0 [noah maicher]
Keyboards

Keyboards are the main data input devices for the computer. The arrangement of keyboard keys is modeled after the typewriter keyboard[1]. The QWERTY keyboard is known as the standard layout of letters, numbers and punctuation. This is because the first six letters on the top row of keys spell QWERTY. In the 1800’s the QWERTY keyboard was designed and made for mechanical typewriters. It was actually designed to slow typists down and to avoid jamming the keys. The Dvordak keyboard is another design which has letters positioned for speed typing.

There is no standard computer keyboard, although several manufacturers imitate the keyboards of PCs (Portable Computer). There are actually three different Portable Computers keyboards: with 84 keys, the original Portable Computer keyboard, also with 84 keys, the AT keyboard, and with 101 keys, the enhanced keyboard. The three differ somewhat in the placement of function keys, the Return key the, Control key, and the Shift keys.

In addition to these keys, IBM keyboard has the following keys: Page Up, Page Down, End, Home, Insert, Pause, Num Lock, Scroll Lock, Break, Caps Lock and Print Screen.

There are many different types of keyboards for the Apple Macintosh. All of the keyboards are called ADB keyboards because they connect to the Apple Desktop bus (ADB). The two main options of Macintosh keyboards are the standard keyboard and the extended keyboard, which has 15 extra special-function keys.[2]

Ibm_keyboard.jpgcomputer-keyboard-01.jpgPortable_computer.jpg

By Noah Maicher

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[1] Source; http://wordnetweb.princeton.edu/perl/webwn?s=computer%20keyboard


[2]Source; http://www.webopedia.com/TERM/K/keyboard.html


[kate]
Scanner

What is a scanner a scanner is a device that captures images. A scanner ``reads'' an image and converts it into a collection of dots that can be stored as a file on a hard disk, a permanent storage device inside many

images.jpg


They are very many scanner one of them is
Image scanner often abbreviated to just scanner is a device that optically scans images, printed text, handwriting , or an object, and converts it to digital images . Common examples found in offices are variations of the desktop (or flatbed) -
Where the document is placed on a glass window for scanning [ cedric duyck]THE MOUSE2425077-wireless-black-computer-mouse-optical-fast-speed-computer-concept.jpg800px-Logitechms48.jpg
A device that controls the movement of the cursor or pointer on a display screen. A mouse is a small object you can roll along a hard, flat surface.

In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons. (Although traditionally a button is typically round or square, modern mice have spring-loaded regions of their top surface that operate switches when pressed down lightly.)
.
Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse's tail, and the fact that one must make it scurry along a surface. The mouse is used to point at things that you want to see. There different mouse’s in the world some with no wire. Amazing right. It is an out put.


So we need the mouse for computers or it would be hard.


www.webopedia.com
www.wikipedia.com